qemu-e2k/kvm.h
Sheng Yang 62a2744ca0 kvm: Flush coalesced MMIO buffer periodly
The default action of coalesced MMIO is, cache the writing in buffer, until:
1. The buffer is full.
2. Or the exit to QEmu due to other reasons.

But this would result in a very late writing in some condition.
1. The each time write to MMIO content is small.
2. The writing interval is big.
3. No need for input or accessing other devices frequently.

This issue was observed in a experimental embbed system. The test image
simply print "test" every 1 seconds. The output in QEmu meets expectation,
but the output in KVM is delayed for seconds.

Per Avi's suggestion, I hooked flushing coalesced MMIO buffer in VGA update
handler. By this way, We don't need vcpu explicit exit to QEmu to
handle this issue.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-02-03 19:47:33 -02:00

144 lines
3.9 KiB
C

/*
* QEMU KVM support
*
* Copyright IBM, Corp. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#ifndef QEMU_KVM_H
#define QEMU_KVM_H
#include "config.h"
#include "qemu-queue.h"
#ifdef CONFIG_KVM
extern int kvm_allowed;
#define kvm_enabled() (kvm_allowed)
#else
#define kvm_enabled() (0)
#endif
struct kvm_run;
/* external API */
int kvm_init(int smp_cpus);
int kvm_init_vcpu(CPUState *env);
int kvm_cpu_exec(CPUState *env);
void kvm_set_phys_mem(target_phys_addr_t start_addr,
ram_addr_t size,
ram_addr_t phys_offset);
int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr,
target_phys_addr_t end_addr);
int kvm_log_start(target_phys_addr_t phys_addr, ram_addr_t size);
int kvm_log_stop(target_phys_addr_t phys_addr, ram_addr_t size);
int kvm_set_migration_log(int enable);
int kvm_has_sync_mmu(void);
int kvm_has_vcpu_events(void);
void kvm_setup_guest_memory(void *start, size_t size);
int kvm_coalesce_mmio_region(target_phys_addr_t start, ram_addr_t size);
int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size);
void kvm_flush_coalesced_mmio_buffer(void);
int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
target_ulong len, int type);
int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
target_ulong len, int type);
void kvm_remove_all_breakpoints(CPUState *current_env);
int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap);
int kvm_pit_in_kernel(void);
int kvm_irqchip_in_kernel(void);
/* internal API */
struct KVMState;
typedef struct KVMState KVMState;
int kvm_ioctl(KVMState *s, int type, ...);
int kvm_vm_ioctl(KVMState *s, int type, ...);
int kvm_vcpu_ioctl(CPUState *env, int type, ...);
/* Arch specific hooks */
int kvm_arch_post_run(CPUState *env, struct kvm_run *run);
int kvm_arch_handle_exit(CPUState *env, struct kvm_run *run);
int kvm_arch_pre_run(CPUState *env, struct kvm_run *run);
int kvm_arch_get_registers(CPUState *env);
int kvm_arch_put_registers(CPUState *env);
int kvm_arch_init(KVMState *s, int smp_cpus);
int kvm_arch_init_vcpu(CPUState *env);
void kvm_arch_reset_vcpu(CPUState *env);
struct kvm_guest_debug;
struct kvm_debug_exit_arch;
struct kvm_sw_breakpoint {
target_ulong pc;
target_ulong saved_insn;
int use_count;
QTAILQ_ENTRY(kvm_sw_breakpoint) entry;
};
QTAILQ_HEAD(kvm_sw_breakpoint_head, kvm_sw_breakpoint);
int kvm_arch_debug(struct kvm_debug_exit_arch *arch_info);
struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,
target_ulong pc);
int kvm_sw_breakpoints_active(CPUState *env);
int kvm_arch_insert_sw_breakpoint(CPUState *current_env,
struct kvm_sw_breakpoint *bp);
int kvm_arch_remove_sw_breakpoint(CPUState *current_env,
struct kvm_sw_breakpoint *bp);
int kvm_arch_insert_hw_breakpoint(target_ulong addr,
target_ulong len, int type);
int kvm_arch_remove_hw_breakpoint(target_ulong addr,
target_ulong len, int type);
void kvm_arch_remove_all_hw_breakpoints(void);
void kvm_arch_update_guest_debug(CPUState *env, struct kvm_guest_debug *dbg);
int kvm_check_extension(KVMState *s, unsigned int extension);
uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function,
int reg);
void kvm_cpu_synchronize_state(CPUState *env);
/* generic hooks - to be moved/refactored once there are more users */
static inline void cpu_synchronize_state(CPUState *env)
{
if (kvm_enabled()) {
kvm_cpu_synchronize_state(env);
}
}
#endif